U.S. Pat. No. 6,678,137 (Mason), which is incorporated by reference herein in its entirety, allegedly recites an “arc fault current interrupting (AFCI) circuit breaker includes a pair of electrical contacts for stopping the flow of electrical current in a protected portion of the distribution circuit. A low pass filter is configured to receive a signal indicative of a voltage across a resistance in the distribution circuit. The low pass filter amplifies the signal and provides the signal to an arc fault detection circuit. The low pass filter includes an input resistance and a feedback resistance. In one embodiment of the invention, the input resistance has a positive temperature coefficient. In another embodiment, the feedback resistance has a negative temperature coefficient. In yet another embodiment, the input resistance has a positive temperature coefficient and the feedback resistance has a negative temperature coefficient. In any of the embodiments, when temperature decreases, the gain provided by the temperature compensation circuit increases due to the temperature coefficients of the input and/or feedback resistors. As a result, the arc fault detection circuitry will maintain a constant sensitivity to arc faults throughout the entire operating temperature range of the AFCI circuit breaker.” See Abstract.
U.S. Pat. No. 6,813,131 (Schmalz), which is incorporated by reference herein in its entirety, allegedly recites a “circuit breaker includes separable contacts, a latchable operating mechanism having a latch member, a bimetal and an arc fault trip assembly. The trip assembly includes a thermistor responsive to bimetal temperature, an amplifier having first and second inputs and an output, a first resistor electrically connected between a second bimetal terminal and the first amplifier input, a second resistor electrically connected in parallel with the thermistor, a third resistor electrically connected in series with that parallel combination, with that series combination being electrically connected between the first amplifier input and the amplifier output. The second amplifier input is referenced to the first bimetal terminal. The amplifier output has a voltage, which is compensated for the bimetal temperature coefficient. The trip assembly provides a trip signal as a function of compensated voltage. A solenoid responds to the trip signal and releases the latch member to trip the separable contacts open.” See Abstract.
U.S. Pat. No. 5,729,145 (Blades), which is incorporated by reference herein in its entirety, allegedly recites that “[a] rcing in an AC power system is detected by monitoring the power waveform for wideband high-frequency noise, and examining the detected noise for patterns of variation in its amplitude synchronized to the power waveform. A narrowband, swept-frequency detector and synchronous averaging may be employed to improve discrimination of arc noise from background interference. An arcing fault interrupter for controlling a single circuit, and a whole house monitor, for detecting arcing anywhere in a house, are described.” See Abstract.